What, if any, are the phase changes?
On Mon, Mar 12, 2012 at 5:39 PM, Chuck Forsberg WA7KGX N2469R <c...@omen.com>wrote: > > > On 03/10/2012 04:44 PM, Mark Spencer wrote: > >> I've done this as well. >> >> I daisy chained several pieces of hp and marconi gear together that all >> had an approx 1k ohm input impedance for the frequency reference and fed >> them from a single 10 Mhz source via t connectors with a 50 ohm terminator >> at the end of the line. Looking at the signal with either a scope or a >> time interval counter I have seen noticeable phase shifts when some of the >> equipment receiving this signal is turned off or on. That being said so >> long as the equipment was not turned off or on the adev of the signal was >> as expected. Your mileage may vary. >> >> Sent from my iPad >> >> On 2012-03-10, at 4:24 PM, Michael Blazer<mbla...@satx.rr.com> wrote: >> >> You may want to take a look at the signal on a scope. Most instruments >>> terminate their reference input. You might actually have 4 50 ohm loads on >>> the Thunderbolt's output and the input voltage might be marginal. If your >>> instruments have both reference input and output, it's better to daisy >>> chain the units. >>> >>> >>> On 3/10/2012 5:10 PM, Chuck Forsberg WA7KGX N2469R wrote: >>> >>>> A month or two ago I had sketched out a simple distribution amp >>>> for my 10 MHz reference. In the meantime I became somewhat >>>> disillusioned about my FE-5680a standards. So I removed the >>>> FE-5680a and disconnected its power supply from the box that >>>> holds the Thunderbolt, power supply, and big line filter. >>>> >>>> I decided to try daisy-chaining the Thunderbolt's 10 MHz output. >>>> I have plenty of hardware left over from the days of 10BaseT networking. >>>> >>>> So I have the Thunderbolt going to a BNC T on the back of my FlexRadio >>>> 1500, >>>> hence to my Advantest U3641 spectrum analyzer, and finally to the >>>> external >>>> reference on my Racal-Dana 1992 nanosecond universal counter. That end >>>> has a 50 ohm termination on the other side of its T connector. >>>> >>>> All three devices seem happy with the 10 MHz they are receiving. >>>> >>>> I connected my Tek 2712 to the end of the chain. It reads +10dbm > +-1db. > > Switching units on/off/ext ref causes less than 1db change in the 10 MHz. > > > > -- > Chuck Forsberg WA7KGX N2469R c...@omen.com www.omen.com > Developer of Industrial ZMODEM(Tm) for Embedded Applications > Omen Technology Inc "The High Reliability Software" > 10255 NW Old Cornelius Pass Portland OR 97231 503-614-0430 > > > ______________________________**_________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/** > mailman/listinfo/time-nuts<https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts> > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.